Satellite communication systems are known and generally well understood. Such systems are typically used in telephone, television and data communications over long distances.
Satellite communication systems are typically used in conjunction with one or more ground stations. Ground stations are usually constructed as high value subsystems able to combine and disperse communication signals routed through the satellite.
Because of the volume of signal traffic typically processed by ground stations, signal traffic may be divided among relatively large numbers of carrier signals. Relatively large dish antenna are often provided to transceive those signals with a desired satellite(s).
Recently, special purpose systems have been developed for transceiving signals with satellites. One example of such a system is the Very Small Aperture Terminal (VSAT) used for the communication of data, voice and video signals, except terrestrial broadcast television.
A VSAT may include a transceiver and antenna (placed outdoors in direct line of sight with the satellite) and an interface unit. The interface unit is typically placed indoors and functions to interface the transceiver with end-user equipment.
One application of VSAT is an Internet/Satellite TV system that provides combined satellite TV and Internet services. The Internet/Satellite TV system interacts with two co-located or close-located satellites. A first satellite may provide two-way Internet access. Internet messages may be received in the 20 GHz band and transmitted on the 30 GHz band.
The second co-located or close-located satellite may provide satellite TV. The second satellite may transmit satellite TV in the 12 GHz band. To provide an extended range of satellite TV channels, multiple satellites may be used. Depending upon position, multiple satellites may be targeted with a nominally coincident beam and or one or more scanned beams.
While the Internet/satellite TV system works well, the three different carriers of 12, 20 and 30 GHz are typically transceived through a dual band antenna and a second, separate antenna for the third band or in a single tri-band antenna using frequency selective surface (FSS) techniques. The use of dual antennas or FSS techniques is expensive and or aesthetically unacceptable in a consumer environment. Further, FSS surfaces may be susceptible to environmental degradation and or fouling.
Competition in the consumer VSAT market has focused attention on minimization of overall costs, improved reliability and ease of installation/use. Accordingly, a need exists for a multi-band antenna system that is cost efficient, compact and conveniently mountable to an exterior of an end-user's home.
Similar efficiencies are also desirable for multi-band terrestrial microwave antenna systems with nominally coincident beams and or one or more scanned beams.
Therefore, it is an object of the invention to provide a co-located multi-band antenna that overcomes deficiencies in the prior art.